PAA five-vehicle crash involving police cars has closed part of the A1 in Newcastle.
The collision happened just before 02:30 BST on the northbound carriageway near junction 75 and the Denton Burn roundabout.
North East Ambulance Service (NEAS) said five people were taken to hospital.
Pictures from the scene show damaged police vehicles and a car seemingly on its side.
The road between junction 73 and 75 is expected to remain shut until the afternoon while a police investigation is carried out, National Highways said, and diversions are in place.
PAAt the scene, BBC Look North reporter Mark Denten said an "extensively damaged" black 4x4 was on its side and debris could be seen scattered across the road.
Four police cars could also be seen, he said, with one a few metres down the road appearing to be the most severely damaged.
BBC Radio Newcastle reporter Rebecca O'Neill said one of the cars was missing its roof.
She said people crossing a footpath near to the scene heard a police helicopter hovering over the area for a "good couple of hours" overnight.
Drivers have been advised to find alternative routes if possible.
The crash hit the morning rush hour with motorists forced to find alternative routes over the River Tyne. It led to 30-to-40 minute queues over the Redheugh Bridge and about 40-minute delays through the Tyne Tunnel.
NEAS said it had sent five crews, a specialist paramedic, a duty officer and two crews from its Hazardous Area Response Team (HART).
